This invention relates to agricultural bedding and tillage implements and specifically to improvements to the disc ridger that is adapted to ridging a set of rows simultaneously while being drawn forward by a tractor such as that patented by Burch in 1963, U.S. Pat. No. 3,088,527. The implement is commonly called a disc bedder in the literature and is also called a disc hipper in some regions. The common form of disc ridger, which is in wide use, has a ridge-forming disc gangs rotatably mounted upon gang support arms, which are arrayed along a transverse frame into a leading and a trailing rank. Each disc gang has a short gang axle with a concave disc mounted at each end. The axle is centrally mounted in a pair of bearings mounted at the end of a gang support arm that has its other end clamped to a transverse frame. The disc gangs are typically mounted with the concave face of each disc tilted upward at an angle of 10 to 20 degrees from vertical and twisted forward at an angle of 20 to 30 degrees from the direction of travel to give it an effective forward cutting angle, however the tilt and twist may vary between much wider limits if desired. There are two disc gangs, each usually having a furrowing disc and a ridging disc, for tilling the valley between each pair of ridges. The gangs follow each other moving soil in opposite directions. The valleys at the outside edges have only one disc gang each, which completes the tillage on a subsequent, adjacent pass in the opposite direction. Some ridgers, particularly those made for narrow rows, have only one disc per gang. The first disc used on the gang will be called a ridging disc; when two discs are used the second will occupy the position further from the center of the row and will be called a furrowing disc.
The disc ridgers were originally made in a configuration that I will refer to as unilateral staggered. In this configuration, all of the leading-rank disc gangs are turned so that the concave side of each disc faces toward one side of the implement while all of the trailing-rank disc gangs are turned so that the concave side of each disc faces toward the other side; and the disc gangs of pairs that move soil into a ridge between themselves are mounted in alternate ranks. This configuraion is inherently resistant to clogging on vegetation and soil, however, it has a severe side draft problem when tilling tough soils.
An answer to the side draft problem was to switch to the opposed configuration; wherein, the disc gangs of pairs that move soil into a ridge between themselves are mounted in the same rank. The problem with the opposed configuration is that it readily clogs on a soil-vegetation mixture in the narrowed throat between pairs of opposed gangs. This problem becomes severe enough for narrow, 30 inch, rows that single-disc gangs rather than double-disc gangs are sometimes used to allow a wider throat.
Both configurations suffer from another severe limitation; neither tills but about half of the area swept by the implement. The central part of each row is left untilled although it may be buried under soil from the furrows; also, neither type is considered suitable for the incorporation of herbicides, fertilizer, or other chemicals into the soil because of a lack of mixing action.
These limitations necessitate the use of another form of tillage before the ridging operation in order to till the soil for disposal of previous crop residues and growing vegetation and, also, for chemical incorporation. After ridging, when the fresh beds have been settled by rain, a different implement is used to till germinating vegetation from the beds and flatten their tops prior to planting; thus, three separate implements have been necessary to ready land for planting on ridges.